On the back of his outstanding performance against New Zealand last week, Sean O’Brien has warned that he is still to reach full fitness.

The Tullow Tank was a colossus in the enthralling defeat to the All Blacks and will be looking for a similar kind of performance against Australia on Saturday.

O’Brien went public with his annoyance at having not been selected for the historic win in Chicago as he battled back from the serious hamstring injury that he suffered against France last February.

After an impressive display against Canada two weeks ago, O’Brien took it to another level against the All Blacks and despite the fact that he looked back to his best, he insisted that there is still more to come from him.

“I didn't have to do much, I suppose,” the flanker said.

“The prep was done during the week. I had prepared myself to play a full game. I was very happy to do that and glad I did.

"I think I'm a little bit off still. I think I've a lot of improvement in myself in different areas. That's why I'm looking forward to this week, to build again on last week and see where we go from here.

“We're obviously expecting a very physical game, I think they've major threats all over the field.

“They have world-class players, such as Pocock, Hooper, Folau, Genia, people who love to be on the ball and over the ball in terms of the back-row they have.

“So they've a very good set-piece, they want to play fast and get over the gainline, so an exciting challenge for us, but a very dangerous side.”

Joe Schmidt admitted that his side had spent little time on the training pitch this week, such was the physical nature of last week's defeat but nevertheless, he is eager to finish the year on a high.

“To be honest it's hard to be super-confident, because we haven't actually put that much together this week,” Schmidt said.

“It was really important that we looked back to try to progress and tidy a few things up. We were probably just one little slip-up with our handling away from scoring a couple of times.

“I'm massively keen that we get a good performance. There's a few things we want to work really hard on this weekend, that will give us a little bit of feedback on ourselves that we can then hopefully take into the Six Nations. Because that's the big tournament we play. It has a context from that perspective.

“You're always chasing a result, you're always wanting to win, and you know that the Wallabies are going to be incredibly tough. They are third-ranked in the world.

“We want to challenge them as much as we can. And we feel if we can just get our performance right and get the bits and pieces of the game that we want to be really strong in.

“If we can get those right then hopefully we're close enough to them, as we were to the All Blacks last week, except there's a small swing in those fine margins, that we actually convert a few of those chances that we create.”